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<pre><span class="sourceLineNo">001</span><a name="line.1"></a>
<span class="sourceLineNo">002</span>/*<a name="line.2"></a>
<span class="sourceLineNo">003</span> * Copyright (C) 2011 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<span class="sourceLineNo">004</span> *<a name="line.4"></a>
<span class="sourceLineNo">005</span> * $Id: AbstractUnsizedContainer.html 769 2013-11-03 18:59:42Z archie.cobbs $<a name="line.5"></a>
<span class="sourceLineNo">006</span> */<a name="line.6"></a>
<span class="sourceLineNo">007</span><a name="line.7"></a>
<span class="sourceLineNo">008</span>package org.dellroad.stuff.vaadin7;<a name="line.8"></a>
<span class="sourceLineNo">009</span><a name="line.9"></a>
<span class="sourceLineNo">010</span>import com.vaadin.data.Container;<a name="line.10"></a>
<span class="sourceLineNo">011</span><a name="line.11"></a>
<span class="sourceLineNo">012</span>import java.util.Collection;<a name="line.12"></a>
<span class="sourceLineNo">013</span>import java.util.List;<a name="line.13"></a>
<span class="sourceLineNo">014</span><a name="line.14"></a>
<span class="sourceLineNo">015</span>/**<a name="line.15"></a>
<span class="sourceLineNo">016</span> * A specialization of {@link AbstractQueryContainer} that doesn't require up-front knowledge of the underlying data's size.<a name="line.16"></a>
<span class="sourceLineNo">017</span> *<a name="line.17"></a>
<span class="sourceLineNo">018</span> * &lt;p&gt;<a name="line.18"></a>
<span class="sourceLineNo">019</span> * Subclasses only need support retrieving a contiguous window of fixed size from the underlying data<a name="line.19"></a>
<span class="sourceLineNo">020</span> * via {@link #queryWindow queryWindow()}; when the requested window goes beyond the end of the underlying data,<a name="line.20"></a>
<span class="sourceLineNo">021</span> * a short or empty result is returned. Based on just this information, this class maintains an estimate of<a name="line.21"></a>
<span class="sourceLineNo">022</span> * the size of the underlying data. Each time that size estimate changes, {@link #handleSizeChange} is invoked<a name="line.22"></a>
<span class="sourceLineNo">023</span> * to schedule a (non-reentrant) property set change notification. Once the end of the underlying data is reached,<a name="line.23"></a>
<span class="sourceLineNo">024</span> * the size is known.<a name="line.24"></a>
<span class="sourceLineNo">025</span> * &lt;/p&gt;<a name="line.25"></a>
<span class="sourceLineNo">026</span> *<a name="line.26"></a>
<span class="sourceLineNo">027</span> * &lt;p&gt;<a name="line.27"></a>
<span class="sourceLineNo">028</span> * If the actual size of the underlying data is constant, this class will eventually find it. If the<a name="line.28"></a>
<span class="sourceLineNo">029</span> * actual size of the underlying data can change (either up or down), this class will adapt accordingly,<a name="line.29"></a>
<span class="sourceLineNo">030</span> * but only when it learns of the new size through an invocation of {@link #queryWindow queryWindow()};<a name="line.30"></a>
<span class="sourceLineNo">031</span> * as this depends on how the container is used, this may not occur for a long time.<a name="line.31"></a>
<span class="sourceLineNo">032</span> * &lt;/p&gt;<a name="line.32"></a>
<span class="sourceLineNo">033</span> *<a name="line.33"></a>
<span class="sourceLineNo">034</span> * &lt;p&gt;<a name="line.34"></a>
<span class="sourceLineNo">035</span> * When used to back a Vaadin table, the user will see a table that automatically grows as the user scrolls<a name="line.35"></a>
<span class="sourceLineNo">036</span> * downward, until the actual end of the data is detected.<a name="line.36"></a>
<span class="sourceLineNo">037</span> * &lt;/p&gt;<a name="line.37"></a>
<span class="sourceLineNo">038</span> *<a name="line.38"></a>
<span class="sourceLineNo">039</span> * @param &lt;T&gt; the type of the Java objects that back each {@link com.vaadin.data.Item} in the container<a name="line.39"></a>
<span class="sourceLineNo">040</span> * @see AbstractQueryContainer<a name="line.40"></a>
<span class="sourceLineNo">041</span> */<a name="line.41"></a>
<span class="sourceLineNo">042</span>@SuppressWarnings("serial")<a name="line.42"></a>
<span class="sourceLineNo">043</span>public abstract class AbstractUnsizedContainer&lt;T&gt; extends AbstractQueryContainer&lt;T&gt; {<a name="line.43"></a>
<span class="sourceLineNo">044</span><a name="line.44"></a>
<span class="sourceLineNo">045</span>    public static final int DEFAULT_WINDOW_SIZE = 50;<a name="line.45"></a>
<span class="sourceLineNo">046</span><a name="line.46"></a>
<span class="sourceLineNo">047</span>    private final int windowSize;<a name="line.47"></a>
<span class="sourceLineNo">048</span><a name="line.48"></a>
<span class="sourceLineNo">049</span>    private long size;<a name="line.49"></a>
<span class="sourceLineNo">050</span>    private boolean sizeIsKnown;<a name="line.50"></a>
<span class="sourceLineNo">051</span><a name="line.51"></a>
<span class="sourceLineNo">052</span>// Constructors<a name="line.52"></a>
<span class="sourceLineNo">053</span><a name="line.53"></a>
<span class="sourceLineNo">054</span>    /**<a name="line.54"></a>
<span class="sourceLineNo">055</span>     * Convenience constructor. Equivalent to:<a name="line.55"></a>
<span class="sourceLineNo">056</span>     *  &lt;blockquote&gt;<a name="line.56"></a>
<span class="sourceLineNo">057</span>     *      {@link #AbstractUnsizedContainer(int) AbstractUnsizedContainer}{@code (}{@link #DEFAULT_WINDOW_SIZE}{@code )}<a name="line.57"></a>
<span class="sourceLineNo">058</span>     *  &lt;/blockquote&gt;<a name="line.58"></a>
<span class="sourceLineNo">059</span>     *<a name="line.59"></a>
<span class="sourceLineNo">060</span>     * &lt;p&gt;<a name="line.60"></a>
<span class="sourceLineNo">061</span>     * After using this constructor, subsequent invocations of {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.61"></a>
<span class="sourceLineNo">062</span>     * and {@link #setProperties setProperties()} are required to define the properties of this container<a name="line.62"></a>
<span class="sourceLineNo">063</span>     * and how to extract them.<a name="line.63"></a>
<span class="sourceLineNo">064</span>     * &lt;/p&gt;<a name="line.64"></a>
<span class="sourceLineNo">065</span>     */<a name="line.65"></a>
<span class="sourceLineNo">066</span>    protected AbstractUnsizedContainer() {<a name="line.66"></a>
<span class="sourceLineNo">067</span>        this(DEFAULT_WINDOW_SIZE);<a name="line.67"></a>
<span class="sourceLineNo">068</span>    }<a name="line.68"></a>
<span class="sourceLineNo">069</span><a name="line.69"></a>
<span class="sourceLineNo">070</span>    /**<a name="line.70"></a>
<span class="sourceLineNo">071</span>     * Convenience constructor. Equivalent to:<a name="line.71"></a>
<span class="sourceLineNo">072</span>     *  &lt;blockquote&gt;<a name="line.72"></a>
<span class="sourceLineNo">073</span>     *      {@link #AbstractUnsizedContainer(int, PropertyExtractor)<a name="line.73"></a>
<span class="sourceLineNo">074</span>     *          AbstractUnsizedContainer}{@code (}{@link #DEFAULT_WINDOW_SIZE}{@code , propertyExtractor)}<a name="line.74"></a>
<span class="sourceLineNo">075</span>     *  &lt;/blockquote&gt;<a name="line.75"></a>
<span class="sourceLineNo">076</span>     *<a name="line.76"></a>
<span class="sourceLineNo">077</span>     * &lt;p&gt;<a name="line.77"></a>
<span class="sourceLineNo">078</span>     * After using this constructor, a subsequent invocation of {@link #setProperties setProperties()} is required<a name="line.78"></a>
<span class="sourceLineNo">079</span>     * to define the properties of this container.<a name="line.79"></a>
<span class="sourceLineNo">080</span>     * &lt;/p&gt;<a name="line.80"></a>
<span class="sourceLineNo">081</span>     *<a name="line.81"></a>
<span class="sourceLineNo">082</span>     * @param propertyExtractor used to extract properties from the underlying Java objects;<a name="line.82"></a>
<span class="sourceLineNo">083</span>     *  may be null but then container is not usable until one is configured via<a name="line.83"></a>
<span class="sourceLineNo">084</span>     * {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.84"></a>
<span class="sourceLineNo">085</span>     */<a name="line.85"></a>
<span class="sourceLineNo">086</span>    protected AbstractUnsizedContainer(PropertyExtractor&lt;? super T&gt; propertyExtractor) {<a name="line.86"></a>
<span class="sourceLineNo">087</span>        this(DEFAULT_WINDOW_SIZE, propertyExtractor);<a name="line.87"></a>
<span class="sourceLineNo">088</span>    }<a name="line.88"></a>
<span class="sourceLineNo">089</span><a name="line.89"></a>
<span class="sourceLineNo">090</span>    /**<a name="line.90"></a>
<span class="sourceLineNo">091</span>     * Convenience constructor. Equivalent to:<a name="line.91"></a>
<span class="sourceLineNo">092</span>     *  &lt;blockquote&gt;<a name="line.92"></a>
<span class="sourceLineNo">093</span>     *      {@link #AbstractUnsizedContainer(int, PropertyExtractor)<a name="line.93"></a>
<span class="sourceLineNo">094</span>     *          AbstractUnsizedContainer}{@code (}{@link #DEFAULT_WINDOW_SIZE}{@code , propertyDefs)}<a name="line.94"></a>
<span class="sourceLineNo">095</span>     *  &lt;/blockquote&gt;<a name="line.95"></a>
<span class="sourceLineNo">096</span>     *<a name="line.96"></a>
<span class="sourceLineNo">097</span>     * &lt;p&gt;<a name="line.97"></a>
<span class="sourceLineNo">098</span>     * After using this constructor, a subsequent invocation of {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.98"></a>
<span class="sourceLineNo">099</span>     * is required to define how to extract the properties of this container; alternately, subclasses can override<a name="line.99"></a>
<span class="sourceLineNo">100</span>     * {@link #getPropertyValue getPropertyValue()}.<a name="line.100"></a>
<span class="sourceLineNo">101</span>     * &lt;/p&gt;<a name="line.101"></a>
<span class="sourceLineNo">102</span>     *<a name="line.102"></a>
<span class="sourceLineNo">103</span>     * @param propertyDefs container property definitions; null is treated like the empty set<a name="line.103"></a>
<span class="sourceLineNo">104</span>     */<a name="line.104"></a>
<span class="sourceLineNo">105</span>    protected AbstractUnsizedContainer(Collection&lt;? extends PropertyDef&lt;?&gt;&gt; propertyDefs) {<a name="line.105"></a>
<span class="sourceLineNo">106</span>        this(DEFAULT_WINDOW_SIZE, propertyDefs);<a name="line.106"></a>
<span class="sourceLineNo">107</span>    }<a name="line.107"></a>
<span class="sourceLineNo">108</span><a name="line.108"></a>
<span class="sourceLineNo">109</span>    /**<a name="line.109"></a>
<span class="sourceLineNo">110</span>     * Convenience constructor. Equivalent to:<a name="line.110"></a>
<span class="sourceLineNo">111</span>     *  &lt;blockquote&gt;<a name="line.111"></a>
<span class="sourceLineNo">112</span>     *      {@link #AbstractUnsizedContainer(int, PropertyExtractor, Collection) AbstractUnsizedContainer}{@code (}{@link<a name="line.112"></a>
<span class="sourceLineNo">113</span>     *          #DEFAULT_WINDOW_SIZE}{@code , propertyExtractor, propertyDefs)}<a name="line.113"></a>
<span class="sourceLineNo">114</span>     *  &lt;/blockquote&gt;<a name="line.114"></a>
<span class="sourceLineNo">115</span>     *<a name="line.115"></a>
<span class="sourceLineNo">116</span>     * @param propertyExtractor used to extract properties from the underlying Java objects;<a name="line.116"></a>
<span class="sourceLineNo">117</span>     *  may be null but then container is not usable until one is configured via<a name="line.117"></a>
<span class="sourceLineNo">118</span>     * {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.118"></a>
<span class="sourceLineNo">119</span>     * @param propertyDefs container property definitions; null is treated like the empty set<a name="line.119"></a>
<span class="sourceLineNo">120</span>     */<a name="line.120"></a>
<span class="sourceLineNo">121</span>    protected AbstractUnsizedContainer(PropertyExtractor&lt;? super T&gt; propertyExtractor,<a name="line.121"></a>
<span class="sourceLineNo">122</span>      Collection&lt;? extends PropertyDef&lt;?&gt;&gt; propertyDefs) {<a name="line.122"></a>
<span class="sourceLineNo">123</span>        this(DEFAULT_WINDOW_SIZE, propertyExtractor, propertyDefs);<a name="line.123"></a>
<span class="sourceLineNo">124</span>    }<a name="line.124"></a>
<span class="sourceLineNo">125</span><a name="line.125"></a>
<span class="sourceLineNo">126</span>    /**<a name="line.126"></a>
<span class="sourceLineNo">127</span>     * Constructor.<a name="line.127"></a>
<span class="sourceLineNo">128</span>     *<a name="line.128"></a>
<span class="sourceLineNo">129</span>     * &lt;p&gt;<a name="line.129"></a>
<span class="sourceLineNo">130</span>     * After using this constructor, subsequent invocations of {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.130"></a>
<span class="sourceLineNo">131</span>     * and {@link #setProperties setProperties()} are required to define the properties of this container<a name="line.131"></a>
<span class="sourceLineNo">132</span>     * and how to extract them.<a name="line.132"></a>
<span class="sourceLineNo">133</span>     * &lt;/p&gt;<a name="line.133"></a>
<span class="sourceLineNo">134</span>     *<a name="line.134"></a>
<span class="sourceLineNo">135</span>     * @param windowSize size of the query window<a name="line.135"></a>
<span class="sourceLineNo">136</span>     * @throws IllegalArgumentException if {@code windowSize} is less than 1<a name="line.136"></a>
<span class="sourceLineNo">137</span>     */<a name="line.137"></a>
<span class="sourceLineNo">138</span>    protected AbstractUnsizedContainer(int windowSize) {<a name="line.138"></a>
<span class="sourceLineNo">139</span>        this(windowSize, (PropertyExtractor&lt;? super T&gt;)null);<a name="line.139"></a>
<span class="sourceLineNo">140</span>    }<a name="line.140"></a>
<span class="sourceLineNo">141</span><a name="line.141"></a>
<span class="sourceLineNo">142</span>    /**<a name="line.142"></a>
<span class="sourceLineNo">143</span>     * Constructor.<a name="line.143"></a>
<span class="sourceLineNo">144</span>     *<a name="line.144"></a>
<span class="sourceLineNo">145</span>     * &lt;p&gt;<a name="line.145"></a>
<span class="sourceLineNo">146</span>     * After using this constructor, a subsequent invocation of {@link #setProperties setProperties()} is required<a name="line.146"></a>
<span class="sourceLineNo">147</span>     * to define the properties of this container.<a name="line.147"></a>
<span class="sourceLineNo">148</span>     * &lt;/p&gt;<a name="line.148"></a>
<span class="sourceLineNo">149</span>     *<a name="line.149"></a>
<span class="sourceLineNo">150</span>     * @param windowSize size of the query window<a name="line.150"></a>
<span class="sourceLineNo">151</span>     * @param propertyExtractor used to extract properties from the underlying Java objects;<a name="line.151"></a>
<span class="sourceLineNo">152</span>     *  may be null but then container is not usable until one is configured via<a name="line.152"></a>
<span class="sourceLineNo">153</span>     * {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.153"></a>
<span class="sourceLineNo">154</span>     * @throws IllegalArgumentException if {@code windowSize} is less than 1<a name="line.154"></a>
<span class="sourceLineNo">155</span>     */<a name="line.155"></a>
<span class="sourceLineNo">156</span>    protected AbstractUnsizedContainer(int windowSize, PropertyExtractor&lt;? super T&gt; propertyExtractor) {<a name="line.156"></a>
<span class="sourceLineNo">157</span>        this(windowSize, propertyExtractor, null);<a name="line.157"></a>
<span class="sourceLineNo">158</span>    }<a name="line.158"></a>
<span class="sourceLineNo">159</span><a name="line.159"></a>
<span class="sourceLineNo">160</span>    /**<a name="line.160"></a>
<span class="sourceLineNo">161</span>     * Constructor.<a name="line.161"></a>
<span class="sourceLineNo">162</span>     *<a name="line.162"></a>
<span class="sourceLineNo">163</span>     * &lt;p&gt;<a name="line.163"></a>
<span class="sourceLineNo">164</span>     * After using this constructor, a subsequent invocation of {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.164"></a>
<span class="sourceLineNo">165</span>     * is required to define how to extract the properties of this container; alternately, subclasses can override<a name="line.165"></a>
<span class="sourceLineNo">166</span>     * {@link #getPropertyValue getPropertyValue()}.<a name="line.166"></a>
<span class="sourceLineNo">167</span>     * &lt;/p&gt;<a name="line.167"></a>
<span class="sourceLineNo">168</span>     *<a name="line.168"></a>
<span class="sourceLineNo">169</span>     * @param windowSize size of the query window<a name="line.169"></a>
<span class="sourceLineNo">170</span>     * @param propertyDefs container property definitions; null is treated like the empty set<a name="line.170"></a>
<span class="sourceLineNo">171</span>     * @throws IllegalArgumentException if {@code windowSize} is less than 1<a name="line.171"></a>
<span class="sourceLineNo">172</span>     */<a name="line.172"></a>
<span class="sourceLineNo">173</span>    protected AbstractUnsizedContainer(int windowSize, Collection&lt;? extends PropertyDef&lt;?&gt;&gt; propertyDefs) {<a name="line.173"></a>
<span class="sourceLineNo">174</span>        this(windowSize, null, propertyDefs);<a name="line.174"></a>
<span class="sourceLineNo">175</span>    }<a name="line.175"></a>
<span class="sourceLineNo">176</span><a name="line.176"></a>
<span class="sourceLineNo">177</span>    /**<a name="line.177"></a>
<span class="sourceLineNo">178</span>     * Constructor.<a name="line.178"></a>
<span class="sourceLineNo">179</span>     *<a name="line.179"></a>
<span class="sourceLineNo">180</span>     * @param windowSize size of the query window (how big of a chunk we query at one time)<a name="line.180"></a>
<span class="sourceLineNo">181</span>     * @param propertyExtractor used to extract properties from the underlying Java objects;<a name="line.181"></a>
<span class="sourceLineNo">182</span>     *  may be null but then container is not usable until one is configured via<a name="line.182"></a>
<span class="sourceLineNo">183</span>     * {@link #setPropertyExtractor setPropertyExtractor()}<a name="line.183"></a>
<span class="sourceLineNo">184</span>     * @param propertyDefs container property definitions; null is treated like the empty set<a name="line.184"></a>
<span class="sourceLineNo">185</span>     * @throws IllegalArgumentException if {@code windowSize} is less than 1<a name="line.185"></a>
<span class="sourceLineNo">186</span>     */<a name="line.186"></a>
<span class="sourceLineNo">187</span>    protected AbstractUnsizedContainer(int windowSize, PropertyExtractor&lt;? super T&gt; propertyExtractor,<a name="line.187"></a>
<span class="sourceLineNo">188</span>      Collection&lt;? extends PropertyDef&lt;?&gt;&gt; propertyDefs) {<a name="line.188"></a>
<span class="sourceLineNo">189</span>        super(propertyExtractor, propertyDefs);<a name="line.189"></a>
<span class="sourceLineNo">190</span>        if (windowSize &lt; 1)<a name="line.190"></a>
<span class="sourceLineNo">191</span>            throw new IllegalArgumentException("windowSize = " + windowSize);<a name="line.191"></a>
<span class="sourceLineNo">192</span>        this.windowSize = windowSize;<a name="line.192"></a>
<span class="sourceLineNo">193</span>    }<a name="line.193"></a>
<span class="sourceLineNo">194</span><a name="line.194"></a>
<span class="sourceLineNo">195</span>    /**<a name="line.195"></a>
<span class="sourceLineNo">196</span>     * Convenience constructor. Equivalent to:<a name="line.196"></a>
<span class="sourceLineNo">197</span>     *  &lt;blockquote&gt;<a name="line.197"></a>
<span class="sourceLineNo">198</span>     *      {@link #AbstractUnsizedContainer(int, Class)<a name="line.198"></a>
<span class="sourceLineNo">199</span>     *          AbstractUnsizedContainer}{@code (}{@link #DEFAULT_WINDOW_SIZE}{@code , type)}<a name="line.199"></a>
<span class="sourceLineNo">200</span>     *  &lt;/blockquote&gt;<a name="line.200"></a>
<span class="sourceLineNo">201</span>     *<a name="line.201"></a>
<span class="sourceLineNo">202</span>     * @param type class to introspect for {@link ProvidesProperty &amp;#64;ProvidesProperty}-annotated fields and methods<a name="line.202"></a>
<span class="sourceLineNo">203</span>     * @throws IllegalArgumentException if {@code type} is null<a name="line.203"></a>
<span class="sourceLineNo">204</span>     * @throws IllegalArgumentException if {@code type} has two {@link ProvidesProperty &amp;#64;ProvidesProperty}<a name="line.204"></a>
<span class="sourceLineNo">205</span>     *  or {@link ProvidesPropertySort &amp;#64;ProvidesPropertySort} annotated methods for the same property<a name="line.205"></a>
<span class="sourceLineNo">206</span>     * @throws IllegalArgumentException if a {@link ProvidesProperty &amp;#64;ProvidesProperty}-annotated method with no<a name="line.206"></a>
<span class="sourceLineNo">207</span>     *  {@linkplain ProvidesProperty#value property name specified} has a name which cannot be interpreted as a bean<a name="line.207"></a>
<span class="sourceLineNo">208</span>     *  property "getter" method<a name="line.208"></a>
<span class="sourceLineNo">209</span>     * @see ProvidesProperty<a name="line.209"></a>
<span class="sourceLineNo">210</span>     * @see ProvidesPropertySort<a name="line.210"></a>
<span class="sourceLineNo">211</span>     * @see ProvidesPropertyScanner<a name="line.211"></a>
<span class="sourceLineNo">212</span>     */<a name="line.212"></a>
<span class="sourceLineNo">213</span>    protected AbstractUnsizedContainer(Class&lt;? super T&gt; type) {<a name="line.213"></a>
<span class="sourceLineNo">214</span>        this(DEFAULT_WINDOW_SIZE, type);<a name="line.214"></a>
<span class="sourceLineNo">215</span>    }<a name="line.215"></a>
<span class="sourceLineNo">216</span><a name="line.216"></a>
<span class="sourceLineNo">217</span>    /**<a name="line.217"></a>
<span class="sourceLineNo">218</span>     * Constructor.<a name="line.218"></a>
<span class="sourceLineNo">219</span>     *<a name="line.219"></a>
<span class="sourceLineNo">220</span>     * &lt;p&gt;<a name="line.220"></a>
<span class="sourceLineNo">221</span>     * Properties will be determined by the {@link ProvidesProperty &amp;#64;ProvidesProperty} and<a name="line.221"></a>
<span class="sourceLineNo">222</span>     * {@link ProvidesPropertySort &amp;#64;ProvidesPropertySort} annotated methods in the given class.<a name="line.222"></a>
<span class="sourceLineNo">223</span>     * &lt;/p&gt;<a name="line.223"></a>
<span class="sourceLineNo">224</span>     *<a name="line.224"></a>
<span class="sourceLineNo">225</span>     * @param windowSize size of the query window<a name="line.225"></a>
<span class="sourceLineNo">226</span>     * @param type class to introspect for annotated methods<a name="line.226"></a>
<span class="sourceLineNo">227</span>     * @throws IllegalArgumentException if {@code type} is null<a name="line.227"></a>
<span class="sourceLineNo">228</span>     * @throws IllegalArgumentException if {@code type} has two {@link ProvidesProperty &amp;#64;ProvidesProperty}<a name="line.228"></a>
<span class="sourceLineNo">229</span>     *  or {@link ProvidesPropertySort &amp;#64;ProvidesPropertySort} annotated methods for the same property<a name="line.229"></a>
<span class="sourceLineNo">230</span>     * @throws IllegalArgumentException if a {@link ProvidesProperty &amp;#64;ProvidesProperty}-annotated method with no<a name="line.230"></a>
<span class="sourceLineNo">231</span>     *  {@linkplain ProvidesProperty#value property name specified} has a name which cannot be interpreted as a bean<a name="line.231"></a>
<span class="sourceLineNo">232</span>     *  property "getter" method<a name="line.232"></a>
<span class="sourceLineNo">233</span>     * @see ProvidesProperty<a name="line.233"></a>
<span class="sourceLineNo">234</span>     * @see ProvidesPropertySort<a name="line.234"></a>
<span class="sourceLineNo">235</span>     * @see ProvidesPropertyScanner<a name="line.235"></a>
<span class="sourceLineNo">236</span>     */<a name="line.236"></a>
<span class="sourceLineNo">237</span>    protected AbstractUnsizedContainer(int windowSize, Class&lt;? super T&gt; type) {<a name="line.237"></a>
<span class="sourceLineNo">238</span>        super(type);<a name="line.238"></a>
<span class="sourceLineNo">239</span>        if (windowSize &lt; 1)<a name="line.239"></a>
<span class="sourceLineNo">240</span>            throw new IllegalArgumentException("windowSize = " + windowSize);<a name="line.240"></a>
<span class="sourceLineNo">241</span>        this.windowSize = windowSize;<a name="line.241"></a>
<span class="sourceLineNo">242</span>    }<a name="line.242"></a>
<span class="sourceLineNo">243</span><a name="line.243"></a>
<span class="sourceLineNo">244</span>    @Override<a name="line.244"></a>
<span class="sourceLineNo">245</span>    protected QueryList&lt;T&gt; query(long hint) {<a name="line.245"></a>
<span class="sourceLineNo">246</span><a name="line.246"></a>
<span class="sourceLineNo">247</span>        // Clip hint value<a name="line.247"></a>
<span class="sourceLineNo">248</span>        hint = Math.min(hint, this.size - 1);<a name="line.248"></a>
<span class="sourceLineNo">249</span>        hint = Math.max(hint, 0);<a name="line.249"></a>
<span class="sourceLineNo">250</span><a name="line.250"></a>
<span class="sourceLineNo">251</span>        // Query underlying data for the window of items centered at "hint"<a name="line.251"></a>
<span class="sourceLineNo">252</span>        final long offset = Math.max(0, hint - this.windowSize / 2);<a name="line.252"></a>
<span class="sourceLineNo">253</span>        final List&lt;? extends T&gt; window = this.queryWindow(offset, this.windowSize);<a name="line.253"></a>
<span class="sourceLineNo">254</span>        final int querySize = window.size();<a name="line.254"></a>
<span class="sourceLineNo">255</span><a name="line.255"></a>
<span class="sourceLineNo">256</span>        // Handle the case where we got an empty window - so the underlying data must have shrunk<a name="line.256"></a>
<span class="sourceLineNo">257</span>        if (querySize &lt;= 0) {<a name="line.257"></a>
<span class="sourceLineNo">258</span><a name="line.258"></a>
<span class="sourceLineNo">259</span>            // If our starting offset was zero, then we know the size must be zero<a name="line.259"></a>
<span class="sourceLineNo">260</span>            if (offset == 0) {<a name="line.260"></a>
<span class="sourceLineNo">261</span>                this.sizeIsKnown = true;<a name="line.261"></a>
<span class="sourceLineNo">262</span>                this.size = 0;<a name="line.262"></a>
<span class="sourceLineNo">263</span>            } else {<a name="line.263"></a>
<span class="sourceLineNo">264</span><a name="line.264"></a>
<span class="sourceLineNo">265</span>                // Guess at what the smaller size is and return a QueryList that will throw an InvalidQueryListException,<a name="line.265"></a>
<span class="sourceLineNo">266</span>                // thereby trigging another probe with a smaller offset. This cycle will repeat until the size is found.<a name="line.266"></a>
<span class="sourceLineNo">267</span>                this.sizeIsKnown = false;<a name="line.267"></a>
<span class="sourceLineNo">268</span>                this.size = this.getSmallerEstimate(offset);<a name="line.268"></a>
<span class="sourceLineNo">269</span>                return new AlwaysInvalidQueryList&lt;T&gt;(this.size);<a name="line.269"></a>
<span class="sourceLineNo">270</span>            }<a name="line.270"></a>
<span class="sourceLineNo">271</span>        }<a name="line.271"></a>
<span class="sourceLineNo">272</span><a name="line.272"></a>
<span class="sourceLineNo">273</span>        // Handle the case where we overlapped the end; now we know the exact size<a name="line.273"></a>
<span class="sourceLineNo">274</span>        if (querySize &lt; this.windowSize) {                  // we overlapped the end; now we know the exact size<a name="line.274"></a>
<span class="sourceLineNo">275</span>            this.size = offset + querySize;<a name="line.275"></a>
<span class="sourceLineNo">276</span>            this.sizeIsKnown = true;<a name="line.276"></a>
<span class="sourceLineNo">277</span>            return new WindowQueryList&lt;T&gt;(offset, window, this.size);<a name="line.277"></a>
<span class="sourceLineNo">278</span>        }<a name="line.278"></a>
<span class="sourceLineNo">279</span><a name="line.279"></a>
<span class="sourceLineNo">280</span>        // Handle the case where we are somewhere in the middle<a name="line.280"></a>
<span class="sourceLineNo">281</span>        if (!this.sizeIsKnown) {<a name="line.281"></a>
<span class="sourceLineNo">282</span><a name="line.282"></a>
<span class="sourceLineNo">283</span>            // Get lower bound on size estimate<a name="line.283"></a>
<span class="sourceLineNo">284</span>            final long lowerBound = offset + querySize;<a name="line.284"></a>
<span class="sourceLineNo">285</span><a name="line.285"></a>
<span class="sourceLineNo">286</span>            // If current size is less than lowerBound + 1, need to expand (the +1 is to leave room to trigger a requery)<a name="line.286"></a>
<span class="sourceLineNo">287</span>            if (this.size &lt; lowerBound + 1) {<a name="line.287"></a>
<span class="sourceLineNo">288</span><a name="line.288"></a>
<span class="sourceLineNo">289</span>                // Get estimate of new larger size<a name="line.289"></a>
<span class="sourceLineNo">290</span>                long largerSize = this.getLargerEstimate(lowerBound);<a name="line.290"></a>
<span class="sourceLineNo">291</span><a name="line.291"></a>
<span class="sourceLineNo">292</span>                // Ensure that it is at least large enough to avoid causing another, redundant subsequent resize. This also<a name="line.292"></a>
<span class="sourceLineNo">293</span>                // ensures that it is strictly larger than the last item in our window so we can always trigger another query.<a name="line.293"></a>
<span class="sourceLineNo">294</span>                largerSize = Math.max(largerSize, lowerBound + this.windowSize);<a name="line.294"></a>
<span class="sourceLineNo">295</span><a name="line.295"></a>
<span class="sourceLineNo">296</span>                // Increase size estimate (maybe)<a name="line.296"></a>
<span class="sourceLineNo">297</span>                this.size = Math.max(this.size, largerSize);<a name="line.297"></a>
<span class="sourceLineNo">298</span>            }<a name="line.298"></a>
<span class="sourceLineNo">299</span>        } else {                                            // we are somewhere in the middle and size is known<a name="line.299"></a>
<span class="sourceLineNo">300</span><a name="line.300"></a>
<span class="sourceLineNo">301</span>            // Detect if the size has grown<a name="line.301"></a>
<span class="sourceLineNo">302</span>            this.size = Math.max(this.size, offset + querySize);<a name="line.302"></a>
<span class="sourceLineNo">303</span>        }<a name="line.303"></a>
<span class="sourceLineNo">304</span><a name="line.304"></a>
<span class="sourceLineNo">305</span>        // Return QueryList based on the window of data we found<a name="line.305"></a>
<span class="sourceLineNo">306</span>        return new WindowQueryList&lt;T&gt;(offset, window, this.size);<a name="line.306"></a>
<span class="sourceLineNo">307</span>    }<a name="line.307"></a>
<span class="sourceLineNo">308</span><a name="line.308"></a>
<span class="sourceLineNo">309</span>    /**<a name="line.309"></a>
<span class="sourceLineNo">310</span>     * Get the window size configured at construction time.<a name="line.310"></a>
<span class="sourceLineNo">311</span>     */<a name="line.311"></a>
<span class="sourceLineNo">312</span>    public int getWindowSize() {<a name="line.312"></a>
<span class="sourceLineNo">313</span>        return this.windowSize;<a name="line.313"></a>
<span class="sourceLineNo">314</span>    }<a name="line.314"></a>
<span class="sourceLineNo">315</span><a name="line.315"></a>
<span class="sourceLineNo">316</span>    /**<a name="line.316"></a>
<span class="sourceLineNo">317</span>     * Get the current size estimate for the underlying data.<a name="line.317"></a>
<span class="sourceLineNo">318</span>     */<a name="line.318"></a>
<span class="sourceLineNo">319</span>    public long getCurrentSizeEstimate() {<a name="line.319"></a>
<span class="sourceLineNo">320</span>        return this.size;<a name="line.320"></a>
<span class="sourceLineNo">321</span>    }<a name="line.321"></a>
<span class="sourceLineNo">322</span><a name="line.322"></a>
<span class="sourceLineNo">323</span>    /**<a name="line.323"></a>
<span class="sourceLineNo">324</span>     * Handle the case where the underlying data's size has suddenly shrunk, so we need to estimate the new size.<a name="line.324"></a>
<span class="sourceLineNo">325</span>     * All we know is that the actual new size is {@code upperBound} or less.<a name="line.325"></a>
<span class="sourceLineNo">326</span>     * This method should guess at the new value and, when called repeatedly, should converge rapidly to zero.<a name="line.326"></a>
<span class="sourceLineNo">327</span>     *<a name="line.327"></a>
<span class="sourceLineNo">328</span>     * &lt;p&gt;<a name="line.328"></a>
<span class="sourceLineNo">329</span>     * Note: this situation will not occur if the underlying data's size never decreases.<a name="line.329"></a>
<span class="sourceLineNo">330</span>     * &lt;/p&gt;<a name="line.330"></a>
<span class="sourceLineNo">331</span>     *<a name="line.331"></a>
<span class="sourceLineNo">332</span>     * &lt;p&gt;<a name="line.332"></a>
<span class="sourceLineNo">333</span>     * The implementation in {@link AbstractUnsizedContainer} returns {@code upperBound * 0.75}.<a name="line.333"></a>
<span class="sourceLineNo">334</span>     * &lt;/p&gt;<a name="line.334"></a>
<span class="sourceLineNo">335</span>     *<a name="line.335"></a>
<span class="sourceLineNo">336</span>     * @param upperBound an upper bound on the size of the underlying data<a name="line.336"></a>
<span class="sourceLineNo">337</span>     * @return estimate of the actual size of the underlying data<a name="line.337"></a>
<span class="sourceLineNo">338</span>     */<a name="line.338"></a>
<span class="sourceLineNo">339</span>    protected long getSmallerEstimate(long upperBound) {<a name="line.339"></a>
<span class="sourceLineNo">340</span>        return (upperBound &gt;&gt; 1) + (upperBound &gt;&gt; 2);<a name="line.340"></a>
<span class="sourceLineNo">341</span>    }<a name="line.341"></a>
<span class="sourceLineNo">342</span><a name="line.342"></a>
<span class="sourceLineNo">343</span>    /**<a name="line.343"></a>
<span class="sourceLineNo">344</span>     * Estimate the size of the underlying data given that {@code lowerBound} is a lower bound.<a name="line.344"></a>
<span class="sourceLineNo">345</span>     * This effectively determines how much data will appear to be "beyond" the current window.<a name="line.345"></a>
<span class="sourceLineNo">346</span>     *<a name="line.346"></a>
<span class="sourceLineNo">347</span>     * &lt;p&gt;<a name="line.347"></a>
<span class="sourceLineNo">348</span>     * The implementation in {@link AbstractUnsizedContainer} returns {@code lowerBound * 1.25}.<a name="line.348"></a>
<span class="sourceLineNo">349</span>     * &lt;/p&gt;<a name="line.349"></a>
<span class="sourceLineNo">350</span>     *<a name="line.350"></a>
<span class="sourceLineNo">351</span>     * @param lowerBound a lower bound on the size of the underlying data<a name="line.351"></a>
<span class="sourceLineNo">352</span>     * @return estimate of the actual size of the underlying data<a name="line.352"></a>
<span class="sourceLineNo">353</span>     */<a name="line.353"></a>
<span class="sourceLineNo">354</span>    protected long getLargerEstimate(long lowerBound) {<a name="line.354"></a>
<span class="sourceLineNo">355</span>        return lowerBound + (lowerBound &gt;&gt; 2);<a name="line.355"></a>
<span class="sourceLineNo">356</span>    }<a name="line.356"></a>
<span class="sourceLineNo">357</span><a name="line.357"></a>
<span class="sourceLineNo">358</span>    @Override<a name="line.358"></a>
<span class="sourceLineNo">359</span>    protected void fireItemSetChange(Container.ItemSetChangeEvent event) {<a name="line.359"></a>
<span class="sourceLineNo">360</span>        this.sizeIsKnown = false;<a name="line.360"></a>
<span class="sourceLineNo">361</span>        super.fireItemSetChange(event);<a name="line.361"></a>
<span class="sourceLineNo">362</span>    }<a name="line.362"></a>
<span class="sourceLineNo">363</span><a name="line.363"></a>
<span class="sourceLineNo">364</span>    /**<a name="line.364"></a>
<span class="sourceLineNo">365</span>     * Query the underlying data for a window of items in the given range. This should return the "window" of underlying<a name="line.365"></a>
<span class="sourceLineNo">366</span>     * data items starting at offset {@code offset} and having at least length {@code length}, or else however many remain.<a name="line.366"></a>
<span class="sourceLineNo">367</span>     * If {@code offset} is greater than or equal to the size of the underlying data, an empty list should be returned.<a name="line.367"></a>
<span class="sourceLineNo">368</span>     *<a name="line.368"></a>
<span class="sourceLineNo">369</span>     * @param offset starting offset for window<a name="line.369"></a>
<span class="sourceLineNo">370</span>     * @param length window size, always greater than zero<a name="line.370"></a>
<span class="sourceLineNo">371</span>     * @return list containing at least {@code length} items in the window starting at offset {@code offset}; or less than<a name="line.371"></a>
<span class="sourceLineNo">372</span>     *  {@code length} items if {@code offset + length} is greater than the size of the underlying data<a name="line.372"></a>
<span class="sourceLineNo">373</span>     */<a name="line.373"></a>
<span class="sourceLineNo">374</span>    protected abstract List&lt;? extends T&gt; queryWindow(long offset, int length);<a name="line.374"></a>
<span class="sourceLineNo">375</span><a name="line.375"></a>
<span class="sourceLineNo">376</span>    /**<a name="line.376"></a>
<span class="sourceLineNo">377</span>     * Emit a property set change notification.<a name="line.377"></a>
<span class="sourceLineNo">378</span>     *<a name="line.378"></a>
<span class="sourceLineNo">379</span>     * &lt;p&gt;<a name="line.379"></a>
<span class="sourceLineNo">380</span>     * Subclasses are required to implement this so that size changes are detected.<a name="line.380"></a>
<span class="sourceLineNo">381</span>     * &lt;/p&gt;<a name="line.381"></a>
<span class="sourceLineNo">382</span>     *<a name="line.382"></a>
<span class="sourceLineNo">383</span>     * &lt;p&gt;<a name="line.383"></a>
<span class="sourceLineNo">384</span>     * Note: to avoid re-entrancy problems, this method should not send out any notifications itself;<a name="line.384"></a>
<span class="sourceLineNo">385</span>     * instead, it must schedule notifications to be delivered later (perhaps in a different thread).<a name="line.385"></a>
<span class="sourceLineNo">386</span>     * &lt;/p&gt;<a name="line.386"></a>
<span class="sourceLineNo">387</span>     */<a name="line.387"></a>
<span class="sourceLineNo">388</span>    @Override<a name="line.388"></a>
<span class="sourceLineNo">389</span>    protected abstract void handleSizeChange();<a name="line.389"></a>
<span class="sourceLineNo">390</span>}<a name="line.390"></a>
<span class="sourceLineNo">391</span><a name="line.391"></a>




























































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